1. Technical Field
The present invention relates to an optical imaging system, more particularly to an optical imaging system that is capable of providing improved resolution.
2. Description of the Related Art
Biotechnology is fast rising as a next-generation industry, and accordingly, various bio-imaging techniques are being developed in the field of measurement systems.
A conventional TIR microscope may be structured to excite a fluorescent material that is dyed into a specimen, by using evanescent waves localized along the depth direction that are created when an incident beam undergoes total reflection at the interface between the specimen and a substrate, and to detect the fluorescence signals emitted from the excited fluorescent material and convert them into an image.
However, with the conventional TIR microscope, it is difficult or impossible to detect molecules or molecule trajectories, etc., in the horizontal direction which are smaller than the resolution limit that can be calculated by Abbe's equation of diffraction.
Thus, there is a need for a TIR microscope that not only provides a high resolution in the depth direction but also provides a high resolution in the horizontal direction.
FIG. 1 illustrates the structure of light incidence in an optical imaging system according to the related art.
Referring to FIG. 1, a conventional optical imaging system may include a substrate 100, a multiple number of dimer nanopillars 110, and a first light source 120.
A specimen dyed with a fluorescent material may be placed on the substrate 100, and the first light source 120 may apply an incident ray on the substrate. Here, the first light source may cause total reflection of the incident ray at the interface between the specimen and the substrate, thereby exciting the fluorescent material and causing the fluorescent material to emit light.
The multiple dimer nanopillars 110 formed on the substrate 100 may be structured such that two nanopillars are near each other. When using dimer nanopillars 110, an incident ray may generate a locally activated surface electric field (a hotspot), and as the fluorescent material is excited by such a hot spot, a higher resolution can be obtained.
FIG. 2 illustrates the fluorescent materials in an optical imaging system according to the related art when a light source is applied.
Referring to FIG. 2, the fluorescent materials are shown as dots. As a light source is applied, the fluorescent materials within a particular area may enter an excited state.
However, the area in which the fluorescent materials are excited cannot be reduced below a particular size, even when dimer nanopillars are used. Thus, there is a limit to the level or resolution that can be provided by a conventional TIR optical imaging system.